Such a vehicle is for instance a motor cycle or cycle. A cycle comprises two wheels which are fitted rotatably to the frame. The front wheel is mounted pivotally in the frame by means of a steering arm and connected to a handlebar. Arranged between the front and rear wheel of the cycle is the pedal system which is connected to the rear wheel for driving with a chain.
A large steering front wheel is desirable for road-holding of the cycle and a large rear wheel is desired for favourable ratios in the transmission between the pedal system and the driven rear wheel. This results in a long cycle. A great drawback hereof is that the cycle cannot easily be transported in a car to for instance a recreation area in order to go on a cycling trip. In addition, the cycle requires a considerable space for storage thereof and this is a great disadvantage for people in small accommodation.
The predecessor of the present known cycle, also known as safety cycle, is the front wheel driver cycle as disclosed in GB-A-650-373. This vehicle comprises two wheels which are mounted rotatably on the frame. The front wheel is mounted pivotally in the frame by means of a steering arm and connected to a handlebar. The pedal system is herein arranged in the hub of the front wheel. The use of a large rear wheel and of a chain for drivable connection of the pedal system to the driven wheel is hereby unnecessary. However, in order to achieve a comfortable speed with such a vehicle, the front wheel should be so large that the rider cannot step off the cycle in a simple and safe manner.
In addition, the pedal system co-displaces with the front wheel during steering. This is uncomfortable and has an adverse effect on the stability of the vehicle.
It is the object of the present invention to provide a compact vehicle and to obviate the above stated drawbacks.
This objective is achieved according to the invention in that said drive shaft is connected rotatably to a part of the frame extending roughly parallel to the steering arm, and a universal coupling part is arranged between the drive shaft and the hub of the wheel wherein the drive shaft is connected drivably to the drive system.
A great advantage of the invention is that a steering wheel is also drivable, wherein the drive shaft does not co-displace with the steering wheel during steering. A small rear wheel can hereby be chosen, whereby a short vehicle is created and wherein the comfort of the typical cycle is retained. The drive shaft can moreover be connected in simple manner to the pedal system because the drive shaft does not co-displace with the steering wheel, whereby a transmission can be chosen such that the front wheel can have a reasonable diameter of for instance 20xe2x80x3 or 28xe2x80x3.
According to a first embodiment according to the invention the drive shaft comprises a primary shaft and a secondary shaft mounted thereon, wherein the pedal shaft of the pedal system is formed by the primary shaft and wherein the primary shaft is coupled drivably to the secondary shaft by means of a gear transmission. This results in a very compact vehicle since the front and rear wheel can be placed practically against each other. Furthermore, a seat position hereby results wherein the pedals are arranged in front of the sitting position of the rider instead of under the sitting position. A saddle can further be provided with a back support. The rider can, as a result of his stance, push against the back support during pedalling whereby a great drive force can be developed.
In a preferred embodiment the universal coupling part comprises a cardan joint. Owing to this universal coupling the rotating and pivoting movement of the steering wheel is linked to the drive shaft connected fixedly in the frame. It is also possible to apply a homokinetic is coupling. In addition, the drive is preferably provided with a freewheel clutch.
According to a further embodiment the vehicle is provided with a drive source arranged in the wheel, such as a battery-fed electric motor or combustion engine.